When you've an automatic gate connected on this kind of device sometime you need to open or close the door using a code.
Assuming your device is 146, and code is 1234 to open or close the door, then you must dial 146, wait and dial 1234# and hangup.
The dialplan below can do it only dialing 150.
Dial 146, send 1234# and hangup call after 3 seconds.
This dialplan can be adapted for other usages as well.